X r railway signaling



' P; H. moms. V RAILWAY S I GNALING. APPLICATION H150 mm. 6. 1916.

Patented 11g. 1,1916,

WITNESSES vstood that" the limits of the block sections PERCY. H; THOMAS, or UrPERL ON' CLAm, memes; as'srerronrof THE ULTIONII SWITCH &: SIGNAL ooMrA'iNiUoF swissvALE', rnn'nsrnvmraqn coRroRArIoN or venusynvnma.

Continuation-of 'application Serial m5. 73,810, filed- ItAiLWAY SIGNAI'JNG;

Specification of Letters Patent.

Patented AugJ, 1916,

m 20,1191a. This-application filed March a, 1916;

Serial No. 82,327;

To all whom it may concern:

Be'itknown that'I, PERCY H. THOMAS, a citizen of 1 the United States, residing at Upper Montelai'r, in the county of Essex ,7 ,5 and State of New J ersey, have inventedcertain new and useful Improvements in Rail v a specification; V

My invention relates to signaling for elec larlyfor'use in such systems.

The present appl cz'ttionv is 'a continuation' of my codingapplication filed June 20,

n'aling. v 'If-will'describe one; form of railway signaling. system embodying my invention, and

will then point out the novel features there},

body ng m inventie ll.

- Referring to the drawing, 1 and 2 designate the track rails of a railway track, whichtrack is divided into awplurality of succes-.

jsive block sections A,1B, etc. As here shown, the limits" of these block sections are determined by' insulated joints'lO inboth of the lines'of track rails, although it is undermav be.definedin otherways; ii

. j q The normal direction of movement of cars or trains along the railway is in the direcerned by a signal S these si als are conwith=a third rail. or trolley -11-, extending" along the railway, and the other terminal is connected with-thetrack rails, of the railway; as here shown, the lastmentioned ter- I minal of the generator G; is connected with the middle point; of an induetivegbond113,}

the two'terminalswf which*are 'connected. q p yam-15' being".- considerably less'than 180V".

Thejarm-lii; is provided with a contact plate 1 lfr'espectively with the ftwo rails'.'- The, purpose of this bond l3' is,as usua1', ;to ;ayq1 q rails.

tric railways, and to relays adapted particug block sections.

I 1913, Serial No. 774,810, for railway sig.-'-

tion indicated by thearrow. Traffic through "afblock section A governed by-asignalsff,

and traflic through block. section B isgovblock section.

.fs'hort-circuiting the trackrails at the points ofconnection ofthe generator G with these Inthe form-ofrailway here shown,fboth' track rallsare included in the circuit for the propulsion*current,:;hence I provide 'adja-, way Signaling, of which the followmg 1s cent the endsof each blocksection inductive beads 12 of a usualand well known type for 60.

the purpose of conducting the propulsion current from.-the track rails of -the adjacent Eachof these bonds 12 comprises as usual a core of magnetic material' I provided with a winding 12, the terminals'cs of the winding being connected with the track rails respectively, and the 'middle point of the winding-of "each bond being connected with the middle. point of the winding of adjacent bond for the adjacent block section. The operation of these inductive bonds 12 is so wellknown that no expla nation is required herein. v

' G is a generator'ofalternating signaling -current, the current from. which differs in frequency from the current delivered by the propulsion generator G Fol-example, the

frequency of the propulsion current from generator G. may. be 25 cycles per second, while the frequency ofthe'signalingcurrent from the generator G may be 60 cycles per;

second; for purposes of this specification I Q will assume these two frequencies for the two currents, although it is understoodthat other frequencies may equally 'well be em- 'ployed. .T-he terminals of the generator G are 'connectedwith transmission'm'ains 14:

which extend along the railway. u I Each block section A, B, etc is provided with a track circuit comprising as usual the 90.

two track rails of the se'ctiom-a source of signaling current, and the relay R. As 7 here shown, the source of signaling current v for each track circuit vis the generator G, v r

a; transformer T-being interposed between the mains 14 and the track-- rails of each Each relay R inthe fform )here shown 7 comprises a movable member '15 mounted to oscillate on a sharp edge'd supportl6. The 10.0

member 15'is providedwith three arms 15, 15",. and 15, the angle between arms, 15?

shownthis bias 1s effected 20 which is adapted to englage with a sprix'ig contact finger The member 15 is capable of assuming a middle position (the position in which member 15 of relay R for block section B is shown in. the drawing) in which position contact 2021 is closed, and is capable of rocking in either direction from the middle position to engagement with a stop or a stop 27, in either of which positions the contact 20-21 is opened. The member 15 is biased by a torque to such position that it engages with stop 22 g as here by a counterweight comprising a screw 28 fixed in one arm of the member and a nut 29 adapted to work on the screw. Twoother torques are exerted on member 15 by currents in two windings 25 and26; one of these torques increases with increase of frequency and the other decreases with increase of frequency, and the difference between these torques at a selected frequency is equal and opposite to the torque exerted by the counterweight 28. As here shown, each winding 25, 26 is in the form of a solenoid and is provided with a longitudinally movable core 23 0112 1 of magnetic material. Each core 23, 2l is operatively connected with the member 15 by a cord 33. or 35, which cords are held in suitable grooves formed in the extremities of arms 15 and 15 respectively.

With the construction just described, it will be seen that if the torques exerted on i the member 15 by the action of cores 23 and 21 are equal, with member 15 in its middle position they'will neutralize each other and the member 15 will be drawn toward and held against the stop 22 by the counterweight 28, 29, so that contact 20-21 will be open; if the difference between the torques produced by cores 24 and with member 15 in its middle position is equal and opposite to the torque produced by the counterweight 28. 29, the member 15 will be drawn to and held in the middle position, because in any other position one of theefiective leyer arms 15* or 15 would be greater than it is in the middle position and the other will be less than in the middle position (owing to the fact that arms 15- and 15 are less than 180 apart) and consequently the difference between the torques produced by the windings would no longer neutralize the torque produced by the C()ll1'ltl3l\\"0\,ll1t2' contact 20. 21 is then closed: and if the relation of the torque produced by cores and 21 is any other than that last specified. the member 15 will be drawn toward and held against one or the other of stops 22 or 27. so that contact 20, 21 is open. In the specific embodiment of my invention shown herein. the length of arm 15? is greater than that of arm 15 by an amount such that when the forces are exerted on these a rms by cores 23 and 21 are equal, the dii'lerencc lit cluded in series with winding 25 is a reactance 30, and included in series with windmg 26 s a condenser 31. The circuit for these windlngs is from track rail 1 through -wire 32, then through the multiple circuit,

one branch of which includes winding 25 and reactance 30, and the other branch of l which includes the winding 26 and the condenser 31, then through wire 34 to track rail 2. In the specific embodunent of my invention shown herein, the multiple circuits of the windings 25 and 26 are so adjusted that when current ofthe signaling frequency flows in these windings, the forces exerted on the cores 23 and 2t are equal, hence at any other frequency the forces exerted on these cores are unequal; this adjustment may be accomplished by providing the same number of turns in the windings 25 and 26 and so adjusting the circuits that the currents in these windings are equal at the signaling frequencyaml unequal at any other frequency, or itmay be accomplished by roviding the windings25 and 26 with di erent numbers of turns and, so adjusting the circuits that at the signaling frequency the currents in the two windings are inversely proportional to the number of turns. In the drawing] have indicated the former method of obtaining the desired adjustment, by indicating that the number of turns in the two windings 25 and 26 are equal.

It .will be seen from the foregoing that I provide means for exerting on the member 15 opposing torques one of which increases with increase of frequency and the other of which decreases with increase of frequency. and means for exerting a third constant torque independent of frequency for balancing the difference between the other two torques at a selected frequency.

Each signal S; S, etc.. is provided with a controlling circuit, which circuit is controlled by contact 2021 of the correspond ing relay. The circuit for signal S is from battery 36 through contact 20 -21. signal S,

fore, indicates clear. When, however. a

block section is occupiedby a car or train \V,

, open by counterweig as bloelrsection wheelsand aides such car or train shunt the signaling current from" relay R of that blocksection, so i that contact -21 or that relay is held t- 28, 29, and signal St, therefore, indicates. stop. I

If, while car or train XV. occupies block sectionvA, the potential, of the propulsion current in rails 1 and-2 of this blocksectionl should be: dilferent,r propulsion current would flow'through thewindings and 26- of relay Ry of this block section. Since,.however, the frequency of; the propulsion current is 25 cycles, the value of this current in winding25 would be greater than the value of this current-in Winding 26 (because as 1 the fife uency decreases the current increasest rough reac'tance and decreases through condenser 31 for given potential);

hence, the torque p'roducedon .member 15 by core 23 would exceed that produced by, core 24 and the propulsion currentwould,

therefore. assist the counterweight 28, 29 to 'hold-contact20 21open. v

In case an alternating --'current,ofa fre'- quencyThigher than 60' cycles. should reach the windings-25 and 26-, thecurrent'in'wind;

ing'26 would 'be greater than at 60 cycles (for a given potential) and the current-in winding 25- would. be less than at 60 cycles.

(for a given potential) hence, the force produced by winding'26 would be greater than that produced by winding 25 at any voltage, and unless the voltage were at the criticalpoint where the difference of torque, with member 15in its middle position is just-slit} ficient to balance the torque of the counter;

' weight, the member 15 would be drawn toward and held against stop 27 so that contact 20 21 would' be held open.

It will be seen frointhe foregoing that I- have provideda relay which is responsive. to

alternating current of one frequency to close its contacts, but is not responsible to alternatingcurrent of anyother frequency;

either higher or lower, t clOSe IitS' contacts. I Although Y I- have herein shown and de- 1 -scribed-onlyonef0rn1 of relay {and only'one 1 track rails of 1 which are included in; the cir I m i i g- I movable, member, tu

stings connected with the track rails l cuiuf' of qt-hegp-ropulsioncurrent;

so I s alternating" I with thd'track rails anclditfeijin'g from the form of railway signaling embodying my invention, it is understood that various.

changes andmodifications, may be made i y. invention,

- ;.l."In combination, an electric railway the alt'erna't'n pro'pulslon current,

signaling cu rreri propulsion current in freqiieiicy v a "relay Lg 7 4: ,3, v adapted to exertltorque in oppositedirec-v tions on said member, meansassociatedi with; v

saidwin'dings for causing the torques to vary at ,different rates with-1 variations of:,--- J,

- frequency, means for exerting onisaid 'member athirdtorque independent of frequency for balancingthediiference between the tivLo first-mentioned torques, at the frequencyiof the signaling current; av signahla controlli-iig, circuitforsaidsignal, and means controlled by said movable member forclosing said balanced in either" directionl 2. In combination, an electric'railway the track rails of which are includedin thecir 'cuit ofthenpropulsion current,- a sourceof j}; alternating propulsion current, a source of alternating signaling current connected with,

the track rails and differing in frequency from the. propulsion current; a relay com 7 prising a movable member having a middlel i, position and capable of movenientin op} posite directions from said niiddle position,

means-for biasing said'inember in one di} rectionfrom'saidmiddle position, tw'o win d-' ings connected in'mult'ipl'e across "the track rails and adapted to exerttorque on the saidmember in opposite directions, means ineluded in circuit. .with said windings for causing the currents therein to yary at dif-g ferent rates w th changes 1n frequency,the clrcuits'of the w ndings and their lever arms being so'proportioned that at the frequency of'the signaling current the difference betorque produced by the biasingg rneansp whereby'at the signaling current frequency I the member occupies its middle position a'nd whereby at any other frequency the meal ber isn'ioved in" one directionor the'jother from the mlddle position; a rallways gnal;

a controlling circuit for said signal, means operatedby said movable member ,for closing said-circuit when in either direction from said middle tioni 1. p m i,

3, In cowhination, an electric ra ilway h track ra ls or which are included in the c 'cuit-of the'propulsi'on current, a source; -alternat1ng PIOPlllSIOH current, a source of 12o current connected witf alternating signaling J v the trackwra'rls and differ ng n frequency fl'OIIldllle:Pl'OPlllfilOH,Cllllellil; a relay com:

prising a movable member ha ving a middle position and capable of movement in oppo l-Q; sitef directions i'froni said middle, position, means fort-biasing said'melnberin one direc V I the ember occupies its n'nddlepositioii and for o d";

111g said circuit whenuthe member is mov tion zfroi'n said middle'positionftwo'windQ j ir'igs connect-ed in'niultiple across thetraclgj 'sald member in opposite directions, the leverraiils gand adapted to producetorqueon thef f 136"" tween the/torques produced by-the said v windings is equal to and opposite to the &

windings fie equal, whereby at the signaling curren frequency the member occuples its middle position and whereby at any other frequency the member is moved in one direction or the other from the middle position; a railway signal; a controlling circuit for ,said signal, and means operated by said movable member for closing said circuit when-the member occupies its middle position and for opening said circuit when the member is oved in either direction from said middle 1 osi'tion.

4. In combination, an electric railway the track rails of which are included in the circuit of the propulsion current, a source of alt rnating propulsion current, a source of alternating sign'aling current connected with the track rails and differing in frequency from the propulsion current; a relay comprising a movable member having a middle position and capable of movement in opposite directions from said middle position,

a means for biasing said member in one direcfrequencies,

tion from said middle position, two windings having equal numbers of turns con-' nected in multiple across the track rails and adapted to produce torque on the said member in opposite directions, the lever arms of the torques produced by said windings being such that when the forces exerted by the windings are equal'the difference between the torques produced by the windings is equal to and opposite to the torque of the biasing means, means included in the circuits of the windings for causing the currents in the windings to be equal at the signaling frequency and unequal at allother whereby at the signaling current frequency the'member occupies its middle position and whereby at any other frequency the member is moved in one direction or the other from the middle position; a railway signal; a controlling circuit for said signal, and means operated by said movable member for'closing said circuit when the member occupies its middle position and ,for opening said circuit when the member is moved in either direction from said middle position.

5. In combination, an electric railway the track rails of which are includedin the circuit of the propulsion current, a source of alternating propulsion current, a source of alternating signaling current differing in opposite to the torque produced by the bias means, means included in the circuits of frequency from the propulsion current; a

'relay comprising a movable member having 4 a middle position and capable of oscillation in both directions from said middle position, means for biasing said member in one direction from said middle position, said memher having two lever arms forming an angle of less than one hundred eighty degrees, two magnetic cores acting respectively on said lever arms, two windings connected in mul-' tiple across the track rails and acting respectively on said lever arms, means in- [cluded' in circuit with said windings for causing the currents therein to vary at difv ferent rates with changes in frequency, the circuits of the windings and the said lever arms being so proportioned that at the frequency of thesignaling current the difference between the torques produced on the movable member by the said cores is equal and opposite to the torque produced by the said biasing means, whereby at the signaling current frequency the member occupies its middle position and whereby at any other frequency the member is moved in one direction or the other from the middle position; a railway signal; a controlling circuit for said signal, and means operated by said movable member for closing said circuit when the member occupies its middle position and for opening said circuit when the member is moved in either direction from said middle position.

(3. In combination, an electric railway the track rails of which are included in the cir- 10c cuit of the propulsion current, a source of alternating propulsion current, a source of alternating signaling current connected with the track rails and differing from the propulsion current in frequency; a relay com- 105 prisinga movable member, tw'o windings connected with the track rails and adapted to exert torques in opposite directions on said member, means associated with said windings for causing the torque exerted by one winding to increase with increase of frequency and the torque exerted by the other winding to erlecrease with increase of frequency,-means for exerting on said member a third torque independent of frequency for balancing the difference between the two first-mentioned torques at the frequency of the signaling current; a railway signal, a circuit for the control of said signal, and means controlled by said movable member for closing said circuit when the torques on said member are balanced and for opening said circuit when the torques on said mem her are unbalanced in either direction.

7. An electric relay comprising a movable member, means for exerting on said member a torque, which increases with increase of frequency, means for exerting on said mem her an opposing torque which decreases with increase of frequency, means for exert- A ing on said member a thirdtorque independent of frequency for balancing the difference betweenthe two first-mentioned torques at a selected frequency, and means controlled. by said member for closing an electric cir- ,cuit when the torques are balanced and for opening the circuitwhen the torques are unbalanced'in either direction.

' 8. A rel y comprising a movable member,

two windings adapted to exert torques on saidmember in opposite directions, means associated with said windings -for causing theitorque exerted by one winding to increase with increase of frequency and; the. torque exerted by the otherwinding to .de-

. crease with increase of frequency, means for exertlng on said member a third torque independent of frequency for balancing'the difference between the two first-mentioned torques at a selected frequency, and means controlled by said member for closing an ;-electric circuit when the torques are balanced it 1 direction. 40

and for opening the circuit when the torques V are unbalanced in eitherdirection.

Sai assoc ated with'said windings for causing the torques exerted thereby to vary at .different' rates with variations in frequency,

means for exerting on said member a .third' torque independent of frequency for'balancing the difference between the, two firstmentioned torques at a selected frequency,

and means controlled by said member for closing an electric circuit when'the torques are balanced and for opening the circuitwhen the torques are unbalanced in either 10. A relay comprising a movable member,='two windings adapted to exert torque on said member in opposite directions, the' effective lever arms of said torques being different, means associated w th sald w1nd-.

ings for causing the forces exerted-on said member by the windings to be equal at a selected frequency and to vary at different rates with variations of frequency,', and

. means fol-exerting on said member a third .torque independent of frequency for balancing the difference between the two firstmentioned torques when the forces'exerted bysaid windings are equal.'

f so

11. A relay comprlsmg a movable member, two windingsedapted toexert torque on said member in opposltedlrectlons, the

effective lever arms of said torques being different, means associated wlth sald windings for causing the forces exerted 'onsaid member by the windings to bear a predetermined relation at a selected frequency and to vary at different rates with variations of frequency, and means for exerting on said member a third torque independentof fre-,

quency for balancing thedifference between v -5 .1 y o pr sing a movable member i i fl PP Q- e Xe rt torques on' i b n opposite dlrections, means the member occupies its intermediate tion but not when themembe-r is'on e he the two first-mentioned torques when the.

forces exerted by saidwindings bear the said predetermined relation.

123A relay comprising a movable ber, two windingshavingequal numbers of.

turns adapted to .exert forces on said member tending to rotate themember in opposite directions, the effective leverarms' at which said forces 'are exerted being differen't, means associated'with said windings for causing the currents in said windings to be equal at one frequency.- and 'to vary at different rates with variations, of frequency, and means" for exerting 'onsaid member a force independent: of frequency forjbalancing the two fir'stmentioned forces when the currentsiin the two windings are equal.

13. A relay comprising a movable member having two lever arms disposediat an angle .of less than one hundred eighty degrees-,-

two windings acting respectively on said lever arms to produce torqu'es on said member ,in' opposite directions,- means associated with, said windingsfor causing the torquesexertedflthereby on the member to vary at different rates with variations of,

frequency,--and means for exerting on said -memb'e'ra third torque independent of frequency for balancing the difference between the two first-mentioned torques at, a

selected frequency.

14. Arelay comprising a member mov-' able in opposite directions from an intermediate position, means for exerting thereon 'two' opposing torques which vary at different rates with variations of. frequency, and meansfor exerting, on said'member athird torque independent of frequency for. balancing the difl'ierenc'e between the two firstmentioned torques at av selected frequency ber two opposing torques which vary at' different rates with variations of frequency,- the structure being such, that the effective length of the lever arm for each torque decreases when the member moves from the intermediate position in the directionof'the force acting 'on' that leverarm and increases when the me-mber'movesin the opposite di-' rection from its intermediate position,'and means for-exerting on said member a third torque independent of frequency for balancing the difference between thev twov first-mentioned torques at a selected frequency whe side of said intermediate position.

13. A relaycomprising a movable; a ber, two windingsadapted to exert'torqueS 39- 105 when the member occupies the said inter direction! i a on said member in opposite directions, an

inductive reactance in series with one winding and'a capacity reactance in series with the'other winding whereby the torque exerted by the first-mentioned winding decreases with increase of frequency and the torque exerted by the second winding increases with' increase offrequency, means for exertingonsaid member a torque inde pendent of frequency for balancing the difference between the two first-mentioned torques ata selectedfrequency, and means controlled by said member for closing an electric circuit when the torques on the member are balanced and for opening the circuit when the-torques are unbalanced in either 17. relay comprising a member in opposite directions from an intermediate position, means for exertingon said member a torque which increases with increase of a frequency, means for exerting on said memher an opposlngtorque which decreases with h increase of frequency, means for exerting on said member a third torque independent of frequency for balancing the difierence between the two first-mentioned torques at a selected frequency, and a contact closed when the member occupies the said intermediate position and opened when the member moves in either direction fromsaid intermediate position.

' -18. In combination, an alternating 'cur-.

rent electric railway the track rails of which are included in the circuit for the propulsion current, asource of alternating signaling current connected with they track rails and differing from the propulsion current in frequency, a relay connected with the track rails and responsive to current of the signaling frequency but not to current substantially higher or substantially lower than the signaling current in frequency, and a signal controlled by said relay.

relay.

movable "'19. In combination with the track rails of a railway, a source of alternating signaling current connected therewith, a relay also connected with said track rails and responsive to current of the signaling frequency but not to current substantially higher or substantially lower than the signaling current in frequency, and a signal controlled byjsaid 20. Incombination with the track rails of a railway, means for supplying alternating signaling current thereto, a relay responsive to current of the signaling frequency but not to current substantially higher or sub-' stantially lower than the signaling current in frequency,'means for energizing said relay from the track rails, and a signal con trolled by said relay.

21. In combination with-the track rails of a railway, means for supplying alternating signaling current thereto; arelay comprisnectedwith the track rails and adapted to rections, means for causing one of said torques to vary directly and the other inversely with variations of frequency of the current 1n the track rails, means for exerting on said member a third torque independent of frequency for balancing the difierence between the two first-mentioned torques at mg a movable member, two windings conexert torques on. said member in opposite dithefrequency vof the signaling current, a 

